


Sacrificium

by Astronut



Category: Harry Potter - J. K. Rowling
Genre: Alternate Universe - Dark, Avada Kedavra, Dark, Gen
Language: English
Status: Completed
Published: 2020-04-20
Updated: 2020-04-20
Packaged: 2021-03-01 22:48:50
Rating: Teen And Up Audiences
Warnings: Major Character Death
Chapters: 1
Words: 2,076
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/23744839
Author URL: https://archiveofourown.org/users/Astronut/pseuds/Astronut
Summary: Would you kill your brother to save the world?
Kudos: 5





	Sacrificium

**Author's Note:**

> Please do not repost without permission. 
> 
> Written in response to a question from a friend: Is there any circumstance where James could kill Sirius or Sirius could kill James? Even if it meant saving the world?

**Sacrificium**

It started as an innocent prank. It ended in untold tragedy. 

James Potter and Sirius Black had never met a locked door that didn’t plead to be unlocked. Through persistence, intelligence, and pure dumb luck they and their friends had spent the last five years secretly scurrying around Hogwarts Castle, coxing out its hidden passages, magic rooms, and buried troves. No secret in the magical school was safe, not with the Marauders on the prowl. Not even those that best remained buried. 

An unholy growl from Sirius’ stomach had lead to a late night sacking of the kitchens. While Remus and Peter had elected to stay in the warm comfort of their beds, Sirius and James braved the cold, dark corridors to feast on warm treacle and spiced pudding, which the house elves had been only too happy to provide. However, the sluggish sleepiness of full tummies had failed to materialize, leaving two wide-awake, sugar fueled teenagers to reject their beds in favor of exploring the lower bowels of Hogwarts’ dungeons. Which is how the two Gryffindor’s found themselves in front of the old stone five levels down and two portraits to the right of the iron statue of Elvinric the Disemboweled. The old _locked_ stone door. 

“Come on, James, hurry up already,” Sirius whispered, keeping an eye on the distant end of the hallway.

“I’ve almost got it,” James spat back. He poked the door once more with his wand and muttered to himself while he examined the stone relief work embedded on either edge of the door. 

“James, just give up already. We’ll come back with Moony and that big book of his. The Slytherin dorms are two staircases back. Think of Snape’s drawers!”

James’ head shot up. “Why the hell would of I want to think of that greasy git’s drawers?”

“For the prank!” The exclamation echoed down the hall, causing both boys to extinguish their wands and listen closely. Ten terse seconds later, Sirius relit his wand and glared at James. “The one for what he said to Evan’s?” Sirius hissed. “It was your idea. I’m not the one that wants to toss all of his underclothes in the Lake, even if they could use a good wash. Probably end up killing the Giant Squid. Poor Squiddo.” 

“She stopped talking to him, you know,” James said softly as he tapped the door again. 

“Who, Squiddo?”

“Not the Giant Squid, you arse. Evans. She stopped talking to Snape.” 

“You really need to stop stalking that girl. The whole knowing her every waking moment thing gets a little creepy.” 

“Shut up and give me a hand. Or two.” James motioned to Sirius to right edge of the doorframe as he took the left. A rope of stonework roses ran along the both edges of the door, the thorns as sharp as pins, and the blossom petals as delicate as glass. The thorns were dense enough that neither edge would be pleasant to the touch, but James’ prodding had discovered four places where the thorns were spaced just so that two sets of still growing hands might, might be able to push the door safely. “Copy what I do, just there. And then we push on three.” 

The boys put action to James’ words but nothing happened. The stone door stood, as it had for centuries, locked in place. “Damn,” Sirius swore. “I thought you had it.” 

“So did I,” James replied, puzzled. As he stepped back to examine the door again his sleeve caught on one of thorns, nicking the skin underneath. James hissed in pain but then gasped. “What the–“

Sirius glanced over in time to see the thorn retract, taking with it a drop of James’ blood. The cold stone vines on the left side of the door began to glow pulsing crimson red. “Huh,” Sirius replied. “That was easy.”

“Says you, you’re not the one bleeding,” James grunted as he charmed a bandage around his wrist. 

“Now I am,” Sirius retorted, pricking his finger on a thorn carved into the left side. 

The pulsing crimson spread until the door was fully encompassed with glowing vines. With deep, unearthly groan, the door slowly sank back, expelling a hiss of stagnate air. 

Sirius whistled. “That’s one hell of a fancy _sacrificium_ lock. My mum just usually goes with the whole spindle theme. Family tradition.”

“Come on! Let’s see what’s in here before anyone comes to see what that noise was. I wouldn’t be surprised if they could hear it all the way up in Slytherin.” 

“Somebody would actually have to be in the Slytherin dorms to hear it,” Sirius sneered, “but we all know that bunch of blood-suckers is probably out frolicking in the night.” 

The boys entered the dark room cautiously, keeping their wands lit and held high. The room beyond was fashioned out of the same grey stone as the ancient door. Like the door, rose vines covered the interior walls. There were no other doors. The room was bare. Sirius blinked, standing in the middle of the empty room. “Well that was a waste of three good pranking hours.” 

James moved closer to inspect the far wall. Here, the vines twisted and intertwined, as if tying the wall itself in place. The stone thorns glistened, as if begging for more blood. He held out his hand, but a cold, sudden draft swept across his neck and gave him pause. “Yeah, maybe it’s a good time to hit the Slytherins now,” he said unsteadily. He turned from the wall to head back out of the disconcerting room. 

“You found something, didn’t you? Another lock?” Sirius asked, stepping forward to take James’ place at the far wall and sticking out his hand. “Are you a Gryffindor or not?” 

At the first sip of blood, the vines once again pulsed a bright crimson, but unlike the door, these vines turned a viscous black as the slowly untwined. 

James grabbed Sirius’s shoulder. “This doesn’t feel right. We need to leave. Now.”

“But we haven’t even...” The sound of dry bones hitting the floor cut Sirius off, as the vines unwrapped, revealing a deeper darkness, with a dozen grinning skulls thrusting out, impaled on thorns as large as poleaxes. One quick glance was all it took for the boys to run back to the old stone door. The old _locked_ stone door. 

“Shit,” Sirius said. “When did that happen?”

“Sirius, this is bad. Really bad. There’s no thorns on the door on this side. Hundreds of them on the walls but none on the door. We can’t unlock it from here!”

Sirius glanced back at the ill-lit, still unwinding vines at the far end of the room. “I think we’re in the antechamber. Whatever is back there, somebody wanted it to stay there. Only one door open at a time.” 

“This is bad. Really, really bad,” James muttered, running his hand through his now sweaty hair. 

“Quit freaking. So we have to figure out how to close the other wall before we can unlock the door? We’ll be out in time for breakfast,” Sirius remarked before stepping away from the door. “If that fails, we’ll just blast a hole in the wall. We’ll probably get detention for a month but we won’t starve.” 

James thrust out an arm to stop Sirius. “Sirius, I know this story. You know it, too.” 

“I don’t know what you’re talking about, Prongs.”

“The Sleeping Death of Salacious Dearth. The evil sorceress Salacious kidnaps the King’s young daughter to use her as a sacrifice to regain her own youth. She gives the girl the Draught of the Living Dead to keep her quiet as she works her spell, but she never accounted for the interaction between the potion and the spell, which rebounds on her, creating the Sleeping Death. The Sleeping Death escapes sorceress’ stronghold, consuming the countryside, living off the dark power given off of dying flesh. In her last dying breaths as she withered away, Salacious manages to contain the Sleeping Death with an intertwining wall of thorns. Years later, a knight storms the wall of thorns, believing the princess to still be asleep inside and while he finds and awakens her, he realizes the only way to reseal the thorn wall is with his own dying flesh.” James frantic recital halted as he caught his breath. “Every one dies, Sirius. Entire towns. Every one except the little girl, because the knight sacrificed himself.” 

Sirius could only stare at his wide-eyed friend. “No, it’s just a kid’s story.” 

“King Arthur and the Knights of the Round Table is a story! The Tale of the Three Brothers is a story! But they all have elements of truth. Merlin and Excalibur. My cloak.” James stabbed his wand at the unrolling vines opening a gaping black maw, “That, that is true!”

The only noise in the expanding chamber was that of the dusty bones dropping to the stone floor as the thorns retracted. 

“We seal it,” Sirius whispered. “We have to seal it.”

“The knight,” James responded, his voice trembling, “the knight had to sacrifice himself to seal the door.” 

“How?”

“I don’t know.” 

Sirius took a deep breath and then approached the hallway that was slowly forming, carpeted with bones of wizards past. “James, you notice anything about these bones?”

James, who had held back, shook his head. “What is it?”

“There’s no wands. Some jewelry, some armor. The clothes are long gone, but there aren’t any wands. Wands don’t decompose.” 

“But how did they get in? I thought _sacrificium_ only worked with magical blood.” 

Sirius sighed and returned to James’ side. “It does. And it took two wizards to open the door. It’ll take two to close it.”

James felt his stomach drop. “The little girl, the princess.” 

Sirius nodded tiredly. “Flip you for it?” 

“No,” James cried in horror. “No! Sirius, this is not something you just flip a knut for!” 

“How else are we going to decide, James? I’d rather die for you than kill you! But you’d do the same! Do you want us to sit here and draw up a list of pros and cons or do you just want to flip the damn knut and be done with it!” 

James shook his head, eyes burning as he blinked in desperation. “No, there’s got to be another way.” 

“Heads or tails?” Sirus asked, his voice hard. He wasn’t going to break. He couldn’t. 

“I won’t”

“Fine, heads you’re the princess and I’m the knight.” He pulled a small bronze knut out of his robe pocket. It glistened in the wand light. “Here goes.” 

Neither boy breathed as the knut shimmered in the air. 

It clinked softly on the stone floor. 

“Tails.” 

A moan echoed in the stone chamber, stirring dust and bone, but it didn’t come from the boys. Whatever lay down the hall of thorns had awoken. 

“Right then,” James whispered. “Better get on with it, Princess.” 

Sirius slowly pointed his wand at James. “James, I...”

“I know, Sirius,” James’ voice trembled. “Do it.” 

Another moan, deeper this time, echoed down the hall. Both boys could now see their breath in the air. 

“Okay, okay. Here we go,” Sirius’ voice cracked and he cleared his throat. Eyes closed, he pointed his shaking wand at his best friend and spoke the words he never thought he’d say. “ _Avada Kedavra_.” 

There was no green flash. If anything, the light from James’ wand had dimmed, but James was still breathing, tears leaking from his eyes as he stared at Sirius. “Again,” he breathed. 

“ _Avada Kedavra_.” 

Again, nothing. 

The moan had gotten louder. 

“ _Avada Kedavra_. _Avada Kedavra_. _Avada Kedavra_!” Sirius screamed, jabbing his wand at James. “James, I can’t! Oh, Merlin, I can’t! I’m sorry!” Sirius sobbed. 

Biting his lip, James raised his own wand as another moan shook the chamber. “Sirius...”

“Please, James, please...”

_“Avada Kedavra_.”

There was no thump of a body hitting the floor. By now, ice had formed over the stone vine-lined walls. The wand lights had dimmed so much that the two sets of tearful, terrified eyes could barely see each other. 

In desperation, both boys raised their wands, friend against friend, and brother against brother. As one, they chanted. 

“ _Avada Kedavra_. _Avada Kedavra_. _Avada Kedavra._ ” 

No green light. 

Nothing but cold, expanding darkness. 

“Never used an Unforgivable Curse before, have you, boy?”

“You need to mean them, Potter!” 

-Bellatrix Lestrange, OotP


End file.
